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1/*
2 * Central processing for nfsd.
3 *
4 * Authors: Olaf Kirch (okir@monad.swb.de)
5 *
6 * Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
7 */
8
9#include <linux/sched.h>
10#include <linux/freezer.h>
11#include <linux/module.h>
12#include <linux/fs_struct.h>
13#include <linux/swap.h>
14#include <linux/nsproxy.h>
15
16#include <linux/sunrpc/stats.h>
17#include <linux/sunrpc/svcsock.h>
18#include <linux/lockd/bind.h>
19#include <linux/nfsacl.h>
20#include <linux/seq_file.h>
21#include <net/net_namespace.h>
22#include "nfsd.h"
23#include "cache.h"
24#include "vfs.h"
25
26#define NFSDDBG_FACILITY NFSDDBG_SVC
27
28extern struct svc_program nfsd_program;
29static int nfsd(void *vrqstp);
30struct timeval nfssvc_boot;
31
32/*
33 * nfsd_mutex protects nfsd_serv -- both the pointer itself and the members
34 * of the svc_serv struct. In particular, ->sv_nrthreads but also to some
35 * extent ->sv_temp_socks and ->sv_permsocks. It also protects nfsdstats.th_cnt
36 *
37 * If (out side the lock) nfsd_serv is non-NULL, then it must point to a
38 * properly initialised 'struct svc_serv' with ->sv_nrthreads > 0. That number
39 * of nfsd threads must exist and each must listed in ->sp_all_threads in each
40 * entry of ->sv_pools[].
41 *
42 * Transitions of the thread count between zero and non-zero are of particular
43 * interest since the svc_serv needs to be created and initialized at that
44 * point, or freed.
45 *
46 * Finally, the nfsd_mutex also protects some of the global variables that are
47 * accessed when nfsd starts and that are settable via the write_* routines in
48 * nfsctl.c. In particular:
49 *
50 * user_recovery_dirname
51 * user_lease_time
52 * nfsd_versions
53 */
54DEFINE_MUTEX(nfsd_mutex);
55struct svc_serv *nfsd_serv;
56
57/*
58 * nfsd_drc_lock protects nfsd_drc_max_pages and nfsd_drc_pages_used.
59 * nfsd_drc_max_pages limits the total amount of memory available for
60 * version 4.1 DRC caches.
61 * nfsd_drc_pages_used tracks the current version 4.1 DRC memory usage.
62 */
63spinlock_t nfsd_drc_lock;
64unsigned int nfsd_drc_max_mem;
65unsigned int nfsd_drc_mem_used;
66
67#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
68static struct svc_stat nfsd_acl_svcstats;
69static struct svc_version * nfsd_acl_version[] = {
70 [2] = &nfsd_acl_version2,
71 [3] = &nfsd_acl_version3,
72};
73
74#define NFSD_ACL_MINVERS 2
75#define NFSD_ACL_NRVERS ARRAY_SIZE(nfsd_acl_version)
76static struct svc_version *nfsd_acl_versions[NFSD_ACL_NRVERS];
77
78static struct svc_program nfsd_acl_program = {
79 .pg_prog = NFS_ACL_PROGRAM,
80 .pg_nvers = NFSD_ACL_NRVERS,
81 .pg_vers = nfsd_acl_versions,
82 .pg_name = "nfsacl",
83 .pg_class = "nfsd",
84 .pg_stats = &nfsd_acl_svcstats,
85 .pg_authenticate = &svc_set_client,
86};
87
88static struct svc_stat nfsd_acl_svcstats = {
89 .program = &nfsd_acl_program,
90};
91#endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */
92
93static struct svc_version * nfsd_version[] = {
94 [2] = &nfsd_version2,
95#if defined(CONFIG_NFSD_V3)
96 [3] = &nfsd_version3,
97#endif
98#if defined(CONFIG_NFSD_V4)
99 [4] = &nfsd_version4,
100#endif
101};
102
103#define NFSD_MINVERS 2
104#define NFSD_NRVERS ARRAY_SIZE(nfsd_version)
105static struct svc_version *nfsd_versions[NFSD_NRVERS];
106
107struct svc_program nfsd_program = {
108#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
109 .pg_next = &nfsd_acl_program,
110#endif
111 .pg_prog = NFS_PROGRAM, /* program number */
112 .pg_nvers = NFSD_NRVERS, /* nr of entries in nfsd_version */
113 .pg_vers = nfsd_versions, /* version table */
114 .pg_name = "nfsd", /* program name */
115 .pg_class = "nfsd", /* authentication class */
116 .pg_stats = &nfsd_svcstats, /* version table */
117 .pg_authenticate = &svc_set_client, /* export authentication */
118
119};
120
121u32 nfsd_supported_minorversion;
122
123int nfsd_vers(int vers, enum vers_op change)
124{
125 if (vers < NFSD_MINVERS || vers >= NFSD_NRVERS)
126 return 0;
127 switch(change) {
128 case NFSD_SET:
129 nfsd_versions[vers] = nfsd_version[vers];
130#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
131 if (vers < NFSD_ACL_NRVERS)
132 nfsd_acl_versions[vers] = nfsd_acl_version[vers];
133#endif
134 break;
135 case NFSD_CLEAR:
136 nfsd_versions[vers] = NULL;
137#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
138 if (vers < NFSD_ACL_NRVERS)
139 nfsd_acl_versions[vers] = NULL;
140#endif
141 break;
142 case NFSD_TEST:
143 return nfsd_versions[vers] != NULL;
144 case NFSD_AVAIL:
145 return nfsd_version[vers] != NULL;
146 }
147 return 0;
148}
149
150int nfsd_minorversion(u32 minorversion, enum vers_op change)
151{
152 if (minorversion > NFSD_SUPPORTED_MINOR_VERSION)
153 return -1;
154 switch(change) {
155 case NFSD_SET:
156 nfsd_supported_minorversion = minorversion;
157 break;
158 case NFSD_CLEAR:
159 if (minorversion == 0)
160 return -1;
161 nfsd_supported_minorversion = minorversion - 1;
162 break;
163 case NFSD_TEST:
164 return minorversion <= nfsd_supported_minorversion;
165 case NFSD_AVAIL:
166 return minorversion <= NFSD_SUPPORTED_MINOR_VERSION;
167 }
168 return 0;
169}
170
171/*
172 * Maximum number of nfsd processes
173 */
174#define NFSD_MAXSERVS 8192
175
176int nfsd_nrthreads(void)
177{
178 int rv = 0;
179 mutex_lock(&nfsd_mutex);
180 if (nfsd_serv)
181 rv = nfsd_serv->sv_nrthreads;
182 mutex_unlock(&nfsd_mutex);
183 return rv;
184}
185
186static int nfsd_init_socks(int port)
187{
188 int error;
189 if (!list_empty(&nfsd_serv->sv_permsocks))
190 return 0;
191
192 error = svc_create_xprt(nfsd_serv, "udp", &init_net, PF_INET, port,
193 SVC_SOCK_DEFAULTS);
194 if (error < 0)
195 return error;
196
197 error = svc_create_xprt(nfsd_serv, "tcp", &init_net, PF_INET, port,
198 SVC_SOCK_DEFAULTS);
199 if (error < 0)
200 return error;
201
202 return 0;
203}
204
205static bool nfsd_up = false;
206
207static int nfsd_startup(unsigned short port, int nrservs)
208{
209 int ret;
210
211 if (nfsd_up)
212 return 0;
213 /*
214 * Readahead param cache - will no-op if it already exists.
215 * (Note therefore results will be suboptimal if number of
216 * threads is modified after nfsd start.)
217 */
218 ret = nfsd_racache_init(2*nrservs);
219 if (ret)
220 return ret;
221 ret = nfsd_init_socks(port);
222 if (ret)
223 goto out_racache;
224 ret = lockd_up(&init_net);
225 if (ret)
226 goto out_racache;
227 ret = nfs4_state_start();
228 if (ret)
229 goto out_lockd;
230 nfsd_up = true;
231 return 0;
232out_lockd:
233 lockd_down(&init_net);
234out_racache:
235 nfsd_racache_shutdown();
236 return ret;
237}
238
239static void nfsd_shutdown(void)
240{
241 /*
242 * write_ports can create the server without actually starting
243 * any threads--if we get shut down before any threads are
244 * started, then nfsd_last_thread will be run before any of this
245 * other initialization has been done.
246 */
247 if (!nfsd_up)
248 return;
249 nfs4_state_shutdown();
250 lockd_down(&init_net);
251 nfsd_racache_shutdown();
252 nfsd_up = false;
253}
254
255static void nfsd_last_thread(struct svc_serv *serv, struct net *net)
256{
257 nfsd_shutdown();
258
259 svc_rpcb_cleanup(serv, net);
260
261 printk(KERN_WARNING "nfsd: last server has exited, flushing export "
262 "cache\n");
263 nfsd_export_flush(net);
264}
265
266void nfsd_reset_versions(void)
267{
268 int found_one = 0;
269 int i;
270
271 for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) {
272 if (nfsd_program.pg_vers[i])
273 found_one = 1;
274 }
275
276 if (!found_one) {
277 for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++)
278 nfsd_program.pg_vers[i] = nfsd_version[i];
279#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
280 for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++)
281 nfsd_acl_program.pg_vers[i] =
282 nfsd_acl_version[i];
283#endif
284 }
285}
286
287/*
288 * Each session guarantees a negotiated per slot memory cache for replies
289 * which in turn consumes memory beyond the v2/v3/v4.0 server. A dedicated
290 * NFSv4.1 server might want to use more memory for a DRC than a machine
291 * with mutiple services.
292 *
293 * Impose a hard limit on the number of pages for the DRC which varies
294 * according to the machines free pages. This is of course only a default.
295 *
296 * For now this is a #defined shift which could be under admin control
297 * in the future.
298 */
299static void set_max_drc(void)
300{
301 #define NFSD_DRC_SIZE_SHIFT 10
302 nfsd_drc_max_mem = (nr_free_buffer_pages()
303 >> NFSD_DRC_SIZE_SHIFT) * PAGE_SIZE;
304 nfsd_drc_mem_used = 0;
305 spin_lock_init(&nfsd_drc_lock);
306 dprintk("%s nfsd_drc_max_mem %u \n", __func__, nfsd_drc_max_mem);
307}
308
309static int nfsd_get_default_max_blksize(void)
310{
311 struct sysinfo i;
312 unsigned long long target;
313 unsigned long ret;
314
315 si_meminfo(&i);
316 target = (i.totalram - i.totalhigh) << PAGE_SHIFT;
317 /*
318 * Aim for 1/4096 of memory per thread This gives 1MB on 4Gig
319 * machines, but only uses 32K on 128M machines. Bottom out at
320 * 8K on 32M and smaller. Of course, this is only a default.
321 */
322 target >>= 12;
323
324 ret = NFSSVC_MAXBLKSIZE;
325 while (ret > target && ret >= 8*1024*2)
326 ret /= 2;
327 return ret;
328}
329
330int nfsd_create_serv(void)
331{
332 int error;
333 struct net *net = current->nsproxy->net_ns;
334
335 WARN_ON(!mutex_is_locked(&nfsd_mutex));
336 if (nfsd_serv) {
337 svc_get(nfsd_serv);
338 return 0;
339 }
340 if (nfsd_max_blksize == 0)
341 nfsd_max_blksize = nfsd_get_default_max_blksize();
342 nfsd_reset_versions();
343 nfsd_serv = svc_create_pooled(&nfsd_program, nfsd_max_blksize,
344 nfsd_last_thread, nfsd, THIS_MODULE);
345 if (nfsd_serv == NULL)
346 return -ENOMEM;
347
348 error = svc_bind(nfsd_serv, net);
349 if (error < 0) {
350 svc_destroy(nfsd_serv);
351 return error;
352 }
353
354 set_max_drc();
355 do_gettimeofday(&nfssvc_boot); /* record boot time */
356 return 0;
357}
358
359int nfsd_nrpools(void)
360{
361 if (nfsd_serv == NULL)
362 return 0;
363 else
364 return nfsd_serv->sv_nrpools;
365}
366
367int nfsd_get_nrthreads(int n, int *nthreads)
368{
369 int i = 0;
370
371 if (nfsd_serv != NULL) {
372 for (i = 0; i < nfsd_serv->sv_nrpools && i < n; i++)
373 nthreads[i] = nfsd_serv->sv_pools[i].sp_nrthreads;
374 }
375
376 return 0;
377}
378
379int nfsd_set_nrthreads(int n, int *nthreads)
380{
381 int i = 0;
382 int tot = 0;
383 int err = 0;
384 struct net *net = &init_net;
385
386 WARN_ON(!mutex_is_locked(&nfsd_mutex));
387
388 if (nfsd_serv == NULL || n <= 0)
389 return 0;
390
391 if (n > nfsd_serv->sv_nrpools)
392 n = nfsd_serv->sv_nrpools;
393
394 /* enforce a global maximum number of threads */
395 tot = 0;
396 for (i = 0; i < n; i++) {
397 if (nthreads[i] > NFSD_MAXSERVS)
398 nthreads[i] = NFSD_MAXSERVS;
399 tot += nthreads[i];
400 }
401 if (tot > NFSD_MAXSERVS) {
402 /* total too large: scale down requested numbers */
403 for (i = 0; i < n && tot > 0; i++) {
404 int new = nthreads[i] * NFSD_MAXSERVS / tot;
405 tot -= (nthreads[i] - new);
406 nthreads[i] = new;
407 }
408 for (i = 0; i < n && tot > 0; i++) {
409 nthreads[i]--;
410 tot--;
411 }
412 }
413
414 /*
415 * There must always be a thread in pool 0; the admin
416 * can't shut down NFS completely using pool_threads.
417 */
418 if (nthreads[0] == 0)
419 nthreads[0] = 1;
420
421 /* apply the new numbers */
422 svc_get(nfsd_serv);
423 for (i = 0; i < n; i++) {
424 err = svc_set_num_threads(nfsd_serv, &nfsd_serv->sv_pools[i],
425 nthreads[i]);
426 if (err)
427 break;
428 }
429 nfsd_destroy(net);
430 return err;
431}
432
433/*
434 * Adjust the number of threads and return the new number of threads.
435 * This is also the function that starts the server if necessary, if
436 * this is the first time nrservs is nonzero.
437 */
438int
439nfsd_svc(unsigned short port, int nrservs)
440{
441 int error;
442 bool nfsd_up_before;
443 struct net *net = &init_net;
444
445 mutex_lock(&nfsd_mutex);
446 dprintk("nfsd: creating service\n");
447 if (nrservs <= 0)
448 nrservs = 0;
449 if (nrservs > NFSD_MAXSERVS)
450 nrservs = NFSD_MAXSERVS;
451 error = 0;
452 if (nrservs == 0 && nfsd_serv == NULL)
453 goto out;
454
455 error = nfsd_create_serv();
456 if (error)
457 goto out;
458
459 nfsd_up_before = nfsd_up;
460
461 error = nfsd_startup(port, nrservs);
462 if (error)
463 goto out_destroy;
464 error = svc_set_num_threads(nfsd_serv, NULL, nrservs);
465 if (error)
466 goto out_shutdown;
467 /* We are holding a reference to nfsd_serv which
468 * we don't want to count in the return value,
469 * so subtract 1
470 */
471 error = nfsd_serv->sv_nrthreads - 1;
472out_shutdown:
473 if (error < 0 && !nfsd_up_before)
474 nfsd_shutdown();
475out_destroy:
476 nfsd_destroy(net); /* Release server */
477out:
478 mutex_unlock(&nfsd_mutex);
479 return error;
480}
481
482
483/*
484 * This is the NFS server kernel thread
485 */
486static int
487nfsd(void *vrqstp)
488{
489 struct svc_rqst *rqstp = (struct svc_rqst *) vrqstp;
490 int err, preverr = 0;
491
492 /* Lock module and set up kernel thread */
493 mutex_lock(&nfsd_mutex);
494
495 /* At this point, the thread shares current->fs
496 * with the init process. We need to create files with a
497 * umask of 0 instead of init's umask. */
498 if (unshare_fs_struct() < 0) {
499 printk("Unable to start nfsd thread: out of memory\n");
500 goto out;
501 }
502
503 current->fs->umask = 0;
504
505 /*
506 * thread is spawned with all signals set to SIG_IGN, re-enable
507 * the ones that will bring down the thread
508 */
509 allow_signal(SIGKILL);
510 allow_signal(SIGHUP);
511 allow_signal(SIGINT);
512 allow_signal(SIGQUIT);
513
514 nfsdstats.th_cnt++;
515 mutex_unlock(&nfsd_mutex);
516
517 /*
518 * We want less throttling in balance_dirty_pages() so that nfs to
519 * localhost doesn't cause nfsd to lock up due to all the client's
520 * dirty pages.
521 */
522 current->flags |= PF_LESS_THROTTLE;
523 set_freezable();
524
525 /*
526 * The main request loop
527 */
528 for (;;) {
529 /*
530 * Find a socket with data available and call its
531 * recvfrom routine.
532 */
533 while ((err = svc_recv(rqstp, 60*60*HZ)) == -EAGAIN)
534 ;
535 if (err == -EINTR)
536 break;
537 else if (err < 0) {
538 if (err != preverr) {
539 printk(KERN_WARNING "%s: unexpected error "
540 "from svc_recv (%d)\n", __func__, -err);
541 preverr = err;
542 }
543 schedule_timeout_uninterruptible(HZ);
544 continue;
545 }
546
547 validate_process_creds();
548 svc_process(rqstp);
549 validate_process_creds();
550 }
551
552 /* Clear signals before calling svc_exit_thread() */
553 flush_signals(current);
554
555 mutex_lock(&nfsd_mutex);
556 nfsdstats.th_cnt --;
557
558out:
559 rqstp->rq_server = NULL;
560
561 /* Release the thread */
562 svc_exit_thread(rqstp);
563
564 nfsd_destroy(&init_net);
565
566 /* Release module */
567 mutex_unlock(&nfsd_mutex);
568 module_put_and_exit(0);
569 return 0;
570}
571
572static __be32 map_new_errors(u32 vers, __be32 nfserr)
573{
574 if (nfserr == nfserr_jukebox && vers == 2)
575 return nfserr_dropit;
576 if (nfserr == nfserr_wrongsec && vers < 4)
577 return nfserr_acces;
578 return nfserr;
579}
580
581int
582nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp)
583{
584 struct svc_procedure *proc;
585 kxdrproc_t xdr;
586 __be32 nfserr;
587 __be32 *nfserrp;
588
589 dprintk("nfsd_dispatch: vers %d proc %d\n",
590 rqstp->rq_vers, rqstp->rq_proc);
591 proc = rqstp->rq_procinfo;
592
593 /*
594 * Give the xdr decoder a chance to change this if it wants
595 * (necessary in the NFSv4.0 compound case)
596 */
597 rqstp->rq_cachetype = proc->pc_cachetype;
598 /* Decode arguments */
599 xdr = proc->pc_decode;
600 if (xdr && !xdr(rqstp, (__be32*)rqstp->rq_arg.head[0].iov_base,
601 rqstp->rq_argp)) {
602 dprintk("nfsd: failed to decode arguments!\n");
603 *statp = rpc_garbage_args;
604 return 1;
605 }
606
607 /* Check whether we have this call in the cache. */
608 switch (nfsd_cache_lookup(rqstp)) {
609 case RC_INTR:
610 case RC_DROPIT:
611 return 0;
612 case RC_REPLY:
613 return 1;
614 case RC_DOIT:;
615 /* do it */
616 }
617
618 /* need to grab the location to store the status, as
619 * nfsv4 does some encoding while processing
620 */
621 nfserrp = rqstp->rq_res.head[0].iov_base
622 + rqstp->rq_res.head[0].iov_len;
623 rqstp->rq_res.head[0].iov_len += sizeof(__be32);
624
625 /* Now call the procedure handler, and encode NFS status. */
626 nfserr = proc->pc_func(rqstp, rqstp->rq_argp, rqstp->rq_resp);
627 nfserr = map_new_errors(rqstp->rq_vers, nfserr);
628 if (nfserr == nfserr_dropit || rqstp->rq_dropme) {
629 dprintk("nfsd: Dropping request; may be revisited later\n");
630 nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
631 return 0;
632 }
633
634 if (rqstp->rq_proc != 0)
635 *nfserrp++ = nfserr;
636
637 /* Encode result.
638 * For NFSv2, additional info is never returned in case of an error.
639 */
640 if (!(nfserr && rqstp->rq_vers == 2)) {
641 xdr = proc->pc_encode;
642 if (xdr && !xdr(rqstp, nfserrp,
643 rqstp->rq_resp)) {
644 /* Failed to encode result. Release cache entry */
645 dprintk("nfsd: failed to encode result!\n");
646 nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
647 *statp = rpc_system_err;
648 return 1;
649 }
650 }
651
652 /* Store reply in cache. */
653 nfsd_cache_update(rqstp, proc->pc_cachetype, statp + 1);
654 return 1;
655}
656
657int nfsd_pool_stats_open(struct inode *inode, struct file *file)
658{
659 int ret;
660 mutex_lock(&nfsd_mutex);
661 if (nfsd_serv == NULL) {
662 mutex_unlock(&nfsd_mutex);
663 return -ENODEV;
664 }
665 /* bump up the psudo refcount while traversing */
666 svc_get(nfsd_serv);
667 ret = svc_pool_stats_open(nfsd_serv, file);
668 mutex_unlock(&nfsd_mutex);
669 return ret;
670}
671
672int nfsd_pool_stats_release(struct inode *inode, struct file *file)
673{
674 int ret = seq_release(inode, file);
675 struct net *net = &init_net;
676
677 mutex_lock(&nfsd_mutex);
678 /* this function really, really should have been called svc_put() */
679 nfsd_destroy(net);
680 mutex_unlock(&nfsd_mutex);
681 return ret;
682}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Central processing for nfsd.
4 *
5 * Authors: Olaf Kirch (okir@monad.swb.de)
6 *
7 * Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
8 */
9
10#include <linux/sched/signal.h>
11#include <linux/freezer.h>
12#include <linux/module.h>
13#include <linux/fs_struct.h>
14#include <linux/swap.h>
15
16#include <linux/sunrpc/stats.h>
17#include <linux/sunrpc/svcsock.h>
18#include <linux/sunrpc/svc_xprt.h>
19#include <linux/lockd/bind.h>
20#include <linux/nfsacl.h>
21#include <linux/seq_file.h>
22#include <linux/inetdevice.h>
23#include <net/addrconf.h>
24#include <net/ipv6.h>
25#include <net/net_namespace.h>
26#include "nfsd.h"
27#include "cache.h"
28#include "vfs.h"
29#include "netns.h"
30#include "filecache.h"
31
32#include "trace.h"
33
34#define NFSDDBG_FACILITY NFSDDBG_SVC
35
36extern struct svc_program nfsd_program;
37static int nfsd(void *vrqstp);
38#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
39static int nfsd_acl_rpcbind_set(struct net *,
40 const struct svc_program *,
41 u32, int,
42 unsigned short,
43 unsigned short);
44static __be32 nfsd_acl_init_request(struct svc_rqst *,
45 const struct svc_program *,
46 struct svc_process_info *);
47#endif
48static int nfsd_rpcbind_set(struct net *,
49 const struct svc_program *,
50 u32, int,
51 unsigned short,
52 unsigned short);
53static __be32 nfsd_init_request(struct svc_rqst *,
54 const struct svc_program *,
55 struct svc_process_info *);
56
57/*
58 * nfsd_mutex protects nn->nfsd_serv -- both the pointer itself and the members
59 * of the svc_serv struct. In particular, ->sv_nrthreads but also to some
60 * extent ->sv_temp_socks and ->sv_permsocks. It also protects nfsdstats.th_cnt
61 *
62 * If (out side the lock) nn->nfsd_serv is non-NULL, then it must point to a
63 * properly initialised 'struct svc_serv' with ->sv_nrthreads > 0. That number
64 * of nfsd threads must exist and each must listed in ->sp_all_threads in each
65 * entry of ->sv_pools[].
66 *
67 * Transitions of the thread count between zero and non-zero are of particular
68 * interest since the svc_serv needs to be created and initialized at that
69 * point, or freed.
70 *
71 * Finally, the nfsd_mutex also protects some of the global variables that are
72 * accessed when nfsd starts and that are settable via the write_* routines in
73 * nfsctl.c. In particular:
74 *
75 * user_recovery_dirname
76 * user_lease_time
77 * nfsd_versions
78 */
79DEFINE_MUTEX(nfsd_mutex);
80
81/*
82 * nfsd_drc_lock protects nfsd_drc_max_pages and nfsd_drc_pages_used.
83 * nfsd_drc_max_pages limits the total amount of memory available for
84 * version 4.1 DRC caches.
85 * nfsd_drc_pages_used tracks the current version 4.1 DRC memory usage.
86 */
87DEFINE_SPINLOCK(nfsd_drc_lock);
88unsigned long nfsd_drc_max_mem;
89unsigned long nfsd_drc_mem_used;
90
91#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
92static struct svc_stat nfsd_acl_svcstats;
93static const struct svc_version *nfsd_acl_version[] = {
94 [2] = &nfsd_acl_version2,
95 [3] = &nfsd_acl_version3,
96};
97
98#define NFSD_ACL_MINVERS 2
99#define NFSD_ACL_NRVERS ARRAY_SIZE(nfsd_acl_version)
100
101static struct svc_program nfsd_acl_program = {
102 .pg_prog = NFS_ACL_PROGRAM,
103 .pg_nvers = NFSD_ACL_NRVERS,
104 .pg_vers = nfsd_acl_version,
105 .pg_name = "nfsacl",
106 .pg_class = "nfsd",
107 .pg_stats = &nfsd_acl_svcstats,
108 .pg_authenticate = &svc_set_client,
109 .pg_init_request = nfsd_acl_init_request,
110 .pg_rpcbind_set = nfsd_acl_rpcbind_set,
111};
112
113static struct svc_stat nfsd_acl_svcstats = {
114 .program = &nfsd_acl_program,
115};
116#endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */
117
118static const struct svc_version *nfsd_version[] = {
119 [2] = &nfsd_version2,
120#if defined(CONFIG_NFSD_V3)
121 [3] = &nfsd_version3,
122#endif
123#if defined(CONFIG_NFSD_V4)
124 [4] = &nfsd_version4,
125#endif
126};
127
128#define NFSD_MINVERS 2
129#define NFSD_NRVERS ARRAY_SIZE(nfsd_version)
130
131struct svc_program nfsd_program = {
132#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
133 .pg_next = &nfsd_acl_program,
134#endif
135 .pg_prog = NFS_PROGRAM, /* program number */
136 .pg_nvers = NFSD_NRVERS, /* nr of entries in nfsd_version */
137 .pg_vers = nfsd_version, /* version table */
138 .pg_name = "nfsd", /* program name */
139 .pg_class = "nfsd", /* authentication class */
140 .pg_stats = &nfsd_svcstats, /* version table */
141 .pg_authenticate = &svc_set_client, /* export authentication */
142 .pg_init_request = nfsd_init_request,
143 .pg_rpcbind_set = nfsd_rpcbind_set,
144};
145
146static bool
147nfsd_support_version(int vers)
148{
149 if (vers >= NFSD_MINVERS && vers < NFSD_NRVERS)
150 return nfsd_version[vers] != NULL;
151 return false;
152}
153
154static bool *
155nfsd_alloc_versions(void)
156{
157 bool *vers = kmalloc_array(NFSD_NRVERS, sizeof(bool), GFP_KERNEL);
158 unsigned i;
159
160 if (vers) {
161 /* All compiled versions are enabled by default */
162 for (i = 0; i < NFSD_NRVERS; i++)
163 vers[i] = nfsd_support_version(i);
164 }
165 return vers;
166}
167
168static bool *
169nfsd_alloc_minorversions(void)
170{
171 bool *vers = kmalloc_array(NFSD_SUPPORTED_MINOR_VERSION + 1,
172 sizeof(bool), GFP_KERNEL);
173 unsigned i;
174
175 if (vers) {
176 /* All minor versions are enabled by default */
177 for (i = 0; i <= NFSD_SUPPORTED_MINOR_VERSION; i++)
178 vers[i] = nfsd_support_version(4);
179 }
180 return vers;
181}
182
183void
184nfsd_netns_free_versions(struct nfsd_net *nn)
185{
186 kfree(nn->nfsd_versions);
187 kfree(nn->nfsd4_minorversions);
188 nn->nfsd_versions = NULL;
189 nn->nfsd4_minorversions = NULL;
190}
191
192static void
193nfsd_netns_init_versions(struct nfsd_net *nn)
194{
195 if (!nn->nfsd_versions) {
196 nn->nfsd_versions = nfsd_alloc_versions();
197 nn->nfsd4_minorversions = nfsd_alloc_minorversions();
198 if (!nn->nfsd_versions || !nn->nfsd4_minorversions)
199 nfsd_netns_free_versions(nn);
200 }
201}
202
203int nfsd_vers(struct nfsd_net *nn, int vers, enum vers_op change)
204{
205 if (vers < NFSD_MINVERS || vers >= NFSD_NRVERS)
206 return 0;
207 switch(change) {
208 case NFSD_SET:
209 if (nn->nfsd_versions)
210 nn->nfsd_versions[vers] = nfsd_support_version(vers);
211 break;
212 case NFSD_CLEAR:
213 nfsd_netns_init_versions(nn);
214 if (nn->nfsd_versions)
215 nn->nfsd_versions[vers] = false;
216 break;
217 case NFSD_TEST:
218 if (nn->nfsd_versions)
219 return nn->nfsd_versions[vers];
220 fallthrough;
221 case NFSD_AVAIL:
222 return nfsd_support_version(vers);
223 }
224 return 0;
225}
226
227static void
228nfsd_adjust_nfsd_versions4(struct nfsd_net *nn)
229{
230 unsigned i;
231
232 for (i = 0; i <= NFSD_SUPPORTED_MINOR_VERSION; i++) {
233 if (nn->nfsd4_minorversions[i])
234 return;
235 }
236 nfsd_vers(nn, 4, NFSD_CLEAR);
237}
238
239int nfsd_minorversion(struct nfsd_net *nn, u32 minorversion, enum vers_op change)
240{
241 if (minorversion > NFSD_SUPPORTED_MINOR_VERSION &&
242 change != NFSD_AVAIL)
243 return -1;
244
245 switch(change) {
246 case NFSD_SET:
247 if (nn->nfsd4_minorversions) {
248 nfsd_vers(nn, 4, NFSD_SET);
249 nn->nfsd4_minorversions[minorversion] =
250 nfsd_vers(nn, 4, NFSD_TEST);
251 }
252 break;
253 case NFSD_CLEAR:
254 nfsd_netns_init_versions(nn);
255 if (nn->nfsd4_minorversions) {
256 nn->nfsd4_minorversions[minorversion] = false;
257 nfsd_adjust_nfsd_versions4(nn);
258 }
259 break;
260 case NFSD_TEST:
261 if (nn->nfsd4_minorversions)
262 return nn->nfsd4_minorversions[minorversion];
263 return nfsd_vers(nn, 4, NFSD_TEST);
264 case NFSD_AVAIL:
265 return minorversion <= NFSD_SUPPORTED_MINOR_VERSION &&
266 nfsd_vers(nn, 4, NFSD_AVAIL);
267 }
268 return 0;
269}
270
271/*
272 * Maximum number of nfsd processes
273 */
274#define NFSD_MAXSERVS 8192
275
276int nfsd_nrthreads(struct net *net)
277{
278 int rv = 0;
279 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
280
281 mutex_lock(&nfsd_mutex);
282 if (nn->nfsd_serv)
283 rv = nn->nfsd_serv->sv_nrthreads;
284 mutex_unlock(&nfsd_mutex);
285 return rv;
286}
287
288static int nfsd_init_socks(struct net *net, const struct cred *cred)
289{
290 int error;
291 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
292
293 if (!list_empty(&nn->nfsd_serv->sv_permsocks))
294 return 0;
295
296 error = svc_create_xprt(nn->nfsd_serv, "udp", net, PF_INET, NFS_PORT,
297 SVC_SOCK_DEFAULTS, cred);
298 if (error < 0)
299 return error;
300
301 error = svc_create_xprt(nn->nfsd_serv, "tcp", net, PF_INET, NFS_PORT,
302 SVC_SOCK_DEFAULTS, cred);
303 if (error < 0)
304 return error;
305
306 return 0;
307}
308
309static int nfsd_users = 0;
310
311static int nfsd_startup_generic(void)
312{
313 int ret;
314
315 if (nfsd_users++)
316 return 0;
317
318 ret = nfsd_file_cache_init();
319 if (ret)
320 goto dec_users;
321
322 ret = nfs4_state_start();
323 if (ret)
324 goto out_file_cache;
325 return 0;
326
327out_file_cache:
328 nfsd_file_cache_shutdown();
329dec_users:
330 nfsd_users--;
331 return ret;
332}
333
334static void nfsd_shutdown_generic(void)
335{
336 if (--nfsd_users)
337 return;
338
339 nfs4_state_shutdown();
340 nfsd_file_cache_shutdown();
341}
342
343static bool nfsd_needs_lockd(struct nfsd_net *nn)
344{
345 return nfsd_vers(nn, 2, NFSD_TEST) || nfsd_vers(nn, 3, NFSD_TEST);
346}
347
348void nfsd_copy_boot_verifier(__be32 verf[2], struct nfsd_net *nn)
349{
350 int seq = 0;
351
352 do {
353 read_seqbegin_or_lock(&nn->boot_lock, &seq);
354 /*
355 * This is opaque to client, so no need to byte-swap. Use
356 * __force to keep sparse happy. y2038 time_t overflow is
357 * irrelevant in this usage
358 */
359 verf[0] = (__force __be32)nn->nfssvc_boot.tv_sec;
360 verf[1] = (__force __be32)nn->nfssvc_boot.tv_nsec;
361 } while (need_seqretry(&nn->boot_lock, seq));
362 done_seqretry(&nn->boot_lock, seq);
363}
364
365static void nfsd_reset_boot_verifier_locked(struct nfsd_net *nn)
366{
367 ktime_get_real_ts64(&nn->nfssvc_boot);
368}
369
370void nfsd_reset_boot_verifier(struct nfsd_net *nn)
371{
372 write_seqlock(&nn->boot_lock);
373 nfsd_reset_boot_verifier_locked(nn);
374 write_sequnlock(&nn->boot_lock);
375}
376
377static int nfsd_startup_net(struct net *net, const struct cred *cred)
378{
379 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
380 int ret;
381
382 if (nn->nfsd_net_up)
383 return 0;
384
385 ret = nfsd_startup_generic();
386 if (ret)
387 return ret;
388 ret = nfsd_init_socks(net, cred);
389 if (ret)
390 goto out_socks;
391
392 if (nfsd_needs_lockd(nn) && !nn->lockd_up) {
393 ret = lockd_up(net, cred);
394 if (ret)
395 goto out_socks;
396 nn->lockd_up = true;
397 }
398
399 ret = nfsd_file_cache_start_net(net);
400 if (ret)
401 goto out_lockd;
402 ret = nfs4_state_start_net(net);
403 if (ret)
404 goto out_filecache;
405
406#ifdef CONFIG_NFSD_V4_2_INTER_SSC
407 nfsd4_ssc_init_umount_work(nn);
408#endif
409 nn->nfsd_net_up = true;
410 return 0;
411
412out_filecache:
413 nfsd_file_cache_shutdown_net(net);
414out_lockd:
415 if (nn->lockd_up) {
416 lockd_down(net);
417 nn->lockd_up = false;
418 }
419out_socks:
420 nfsd_shutdown_generic();
421 return ret;
422}
423
424static void nfsd_shutdown_net(struct net *net)
425{
426 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
427
428 nfsd_file_cache_shutdown_net(net);
429 nfs4_state_shutdown_net(net);
430 if (nn->lockd_up) {
431 lockd_down(net);
432 nn->lockd_up = false;
433 }
434 nn->nfsd_net_up = false;
435 nfsd_shutdown_generic();
436}
437
438static int nfsd_inetaddr_event(struct notifier_block *this, unsigned long event,
439 void *ptr)
440{
441 struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
442 struct net_device *dev = ifa->ifa_dev->dev;
443 struct net *net = dev_net(dev);
444 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
445 struct sockaddr_in sin;
446
447 if ((event != NETDEV_DOWN) ||
448 !atomic_inc_not_zero(&nn->ntf_refcnt))
449 goto out;
450
451 if (nn->nfsd_serv) {
452 dprintk("nfsd_inetaddr_event: removed %pI4\n", &ifa->ifa_local);
453 sin.sin_family = AF_INET;
454 sin.sin_addr.s_addr = ifa->ifa_local;
455 svc_age_temp_xprts_now(nn->nfsd_serv, (struct sockaddr *)&sin);
456 }
457 atomic_dec(&nn->ntf_refcnt);
458 wake_up(&nn->ntf_wq);
459
460out:
461 return NOTIFY_DONE;
462}
463
464static struct notifier_block nfsd_inetaddr_notifier = {
465 .notifier_call = nfsd_inetaddr_event,
466};
467
468#if IS_ENABLED(CONFIG_IPV6)
469static int nfsd_inet6addr_event(struct notifier_block *this,
470 unsigned long event, void *ptr)
471{
472 struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
473 struct net_device *dev = ifa->idev->dev;
474 struct net *net = dev_net(dev);
475 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
476 struct sockaddr_in6 sin6;
477
478 if ((event != NETDEV_DOWN) ||
479 !atomic_inc_not_zero(&nn->ntf_refcnt))
480 goto out;
481
482 if (nn->nfsd_serv) {
483 dprintk("nfsd_inet6addr_event: removed %pI6\n", &ifa->addr);
484 sin6.sin6_family = AF_INET6;
485 sin6.sin6_addr = ifa->addr;
486 if (ipv6_addr_type(&sin6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
487 sin6.sin6_scope_id = ifa->idev->dev->ifindex;
488 svc_age_temp_xprts_now(nn->nfsd_serv, (struct sockaddr *)&sin6);
489 }
490 atomic_dec(&nn->ntf_refcnt);
491 wake_up(&nn->ntf_wq);
492out:
493 return NOTIFY_DONE;
494}
495
496static struct notifier_block nfsd_inet6addr_notifier = {
497 .notifier_call = nfsd_inet6addr_event,
498};
499#endif
500
501/* Only used under nfsd_mutex, so this atomic may be overkill: */
502static atomic_t nfsd_notifier_refcount = ATOMIC_INIT(0);
503
504static void nfsd_last_thread(struct svc_serv *serv, struct net *net)
505{
506 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
507
508 atomic_dec(&nn->ntf_refcnt);
509 /* check if the notifier still has clients */
510 if (atomic_dec_return(&nfsd_notifier_refcount) == 0) {
511 unregister_inetaddr_notifier(&nfsd_inetaddr_notifier);
512#if IS_ENABLED(CONFIG_IPV6)
513 unregister_inet6addr_notifier(&nfsd_inet6addr_notifier);
514#endif
515 }
516 wait_event(nn->ntf_wq, atomic_read(&nn->ntf_refcnt) == 0);
517
518 /*
519 * write_ports can create the server without actually starting
520 * any threads--if we get shut down before any threads are
521 * started, then nfsd_last_thread will be run before any of this
522 * other initialization has been done except the rpcb information.
523 */
524 svc_rpcb_cleanup(serv, net);
525 if (!nn->nfsd_net_up)
526 return;
527
528 nfsd_shutdown_net(net);
529 pr_info("nfsd: last server has exited, flushing export cache\n");
530 nfsd_export_flush(net);
531}
532
533void nfsd_reset_versions(struct nfsd_net *nn)
534{
535 int i;
536
537 for (i = 0; i < NFSD_NRVERS; i++)
538 if (nfsd_vers(nn, i, NFSD_TEST))
539 return;
540
541 for (i = 0; i < NFSD_NRVERS; i++)
542 if (i != 4)
543 nfsd_vers(nn, i, NFSD_SET);
544 else {
545 int minor = 0;
546 while (nfsd_minorversion(nn, minor, NFSD_SET) >= 0)
547 minor++;
548 }
549}
550
551/*
552 * Each session guarantees a negotiated per slot memory cache for replies
553 * which in turn consumes memory beyond the v2/v3/v4.0 server. A dedicated
554 * NFSv4.1 server might want to use more memory for a DRC than a machine
555 * with mutiple services.
556 *
557 * Impose a hard limit on the number of pages for the DRC which varies
558 * according to the machines free pages. This is of course only a default.
559 *
560 * For now this is a #defined shift which could be under admin control
561 * in the future.
562 */
563static void set_max_drc(void)
564{
565 #define NFSD_DRC_SIZE_SHIFT 7
566 nfsd_drc_max_mem = (nr_free_buffer_pages()
567 >> NFSD_DRC_SIZE_SHIFT) * PAGE_SIZE;
568 nfsd_drc_mem_used = 0;
569 dprintk("%s nfsd_drc_max_mem %lu \n", __func__, nfsd_drc_max_mem);
570}
571
572static int nfsd_get_default_max_blksize(void)
573{
574 struct sysinfo i;
575 unsigned long long target;
576 unsigned long ret;
577
578 si_meminfo(&i);
579 target = (i.totalram - i.totalhigh) << PAGE_SHIFT;
580 /*
581 * Aim for 1/4096 of memory per thread This gives 1MB on 4Gig
582 * machines, but only uses 32K on 128M machines. Bottom out at
583 * 8K on 32M and smaller. Of course, this is only a default.
584 */
585 target >>= 12;
586
587 ret = NFSSVC_MAXBLKSIZE;
588 while (ret > target && ret >= 8*1024*2)
589 ret /= 2;
590 return ret;
591}
592
593static const struct svc_serv_ops nfsd_thread_sv_ops = {
594 .svo_shutdown = nfsd_last_thread,
595 .svo_function = nfsd,
596 .svo_enqueue_xprt = svc_xprt_do_enqueue,
597 .svo_setup = svc_set_num_threads,
598 .svo_module = THIS_MODULE,
599};
600
601static void nfsd_complete_shutdown(struct net *net)
602{
603 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
604
605 WARN_ON(!mutex_is_locked(&nfsd_mutex));
606
607 nn->nfsd_serv = NULL;
608 complete(&nn->nfsd_shutdown_complete);
609}
610
611void nfsd_shutdown_threads(struct net *net)
612{
613 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
614 struct svc_serv *serv;
615
616 mutex_lock(&nfsd_mutex);
617 serv = nn->nfsd_serv;
618 if (serv == NULL) {
619 mutex_unlock(&nfsd_mutex);
620 return;
621 }
622
623 svc_get(serv);
624 /* Kill outstanding nfsd threads */
625 serv->sv_ops->svo_setup(serv, NULL, 0);
626 nfsd_destroy(net);
627 mutex_unlock(&nfsd_mutex);
628 /* Wait for shutdown of nfsd_serv to complete */
629 wait_for_completion(&nn->nfsd_shutdown_complete);
630}
631
632bool i_am_nfsd(void)
633{
634 return kthread_func(current) == nfsd;
635}
636
637int nfsd_create_serv(struct net *net)
638{
639 int error;
640 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
641
642 WARN_ON(!mutex_is_locked(&nfsd_mutex));
643 if (nn->nfsd_serv) {
644 svc_get(nn->nfsd_serv);
645 return 0;
646 }
647 if (nfsd_max_blksize == 0)
648 nfsd_max_blksize = nfsd_get_default_max_blksize();
649 nfsd_reset_versions(nn);
650 nn->nfsd_serv = svc_create_pooled(&nfsd_program, nfsd_max_blksize,
651 &nfsd_thread_sv_ops);
652 if (nn->nfsd_serv == NULL)
653 return -ENOMEM;
654 init_completion(&nn->nfsd_shutdown_complete);
655
656 nn->nfsd_serv->sv_maxconn = nn->max_connections;
657 error = svc_bind(nn->nfsd_serv, net);
658 if (error < 0) {
659 svc_destroy(nn->nfsd_serv);
660 nfsd_complete_shutdown(net);
661 return error;
662 }
663
664 set_max_drc();
665 /* check if the notifier is already set */
666 if (atomic_inc_return(&nfsd_notifier_refcount) == 1) {
667 register_inetaddr_notifier(&nfsd_inetaddr_notifier);
668#if IS_ENABLED(CONFIG_IPV6)
669 register_inet6addr_notifier(&nfsd_inet6addr_notifier);
670#endif
671 }
672 atomic_inc(&nn->ntf_refcnt);
673 nfsd_reset_boot_verifier(nn);
674 return 0;
675}
676
677int nfsd_nrpools(struct net *net)
678{
679 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
680
681 if (nn->nfsd_serv == NULL)
682 return 0;
683 else
684 return nn->nfsd_serv->sv_nrpools;
685}
686
687int nfsd_get_nrthreads(int n, int *nthreads, struct net *net)
688{
689 int i = 0;
690 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
691
692 if (nn->nfsd_serv != NULL) {
693 for (i = 0; i < nn->nfsd_serv->sv_nrpools && i < n; i++)
694 nthreads[i] = nn->nfsd_serv->sv_pools[i].sp_nrthreads;
695 }
696
697 return 0;
698}
699
700void nfsd_destroy(struct net *net)
701{
702 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
703 int destroy = (nn->nfsd_serv->sv_nrthreads == 1);
704
705 if (destroy)
706 svc_shutdown_net(nn->nfsd_serv, net);
707 svc_destroy(nn->nfsd_serv);
708 if (destroy)
709 nfsd_complete_shutdown(net);
710}
711
712int nfsd_set_nrthreads(int n, int *nthreads, struct net *net)
713{
714 int i = 0;
715 int tot = 0;
716 int err = 0;
717 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
718
719 WARN_ON(!mutex_is_locked(&nfsd_mutex));
720
721 if (nn->nfsd_serv == NULL || n <= 0)
722 return 0;
723
724 if (n > nn->nfsd_serv->sv_nrpools)
725 n = nn->nfsd_serv->sv_nrpools;
726
727 /* enforce a global maximum number of threads */
728 tot = 0;
729 for (i = 0; i < n; i++) {
730 nthreads[i] = min(nthreads[i], NFSD_MAXSERVS);
731 tot += nthreads[i];
732 }
733 if (tot > NFSD_MAXSERVS) {
734 /* total too large: scale down requested numbers */
735 for (i = 0; i < n && tot > 0; i++) {
736 int new = nthreads[i] * NFSD_MAXSERVS / tot;
737 tot -= (nthreads[i] - new);
738 nthreads[i] = new;
739 }
740 for (i = 0; i < n && tot > 0; i++) {
741 nthreads[i]--;
742 tot--;
743 }
744 }
745
746 /*
747 * There must always be a thread in pool 0; the admin
748 * can't shut down NFS completely using pool_threads.
749 */
750 if (nthreads[0] == 0)
751 nthreads[0] = 1;
752
753 /* apply the new numbers */
754 svc_get(nn->nfsd_serv);
755 for (i = 0; i < n; i++) {
756 err = nn->nfsd_serv->sv_ops->svo_setup(nn->nfsd_serv,
757 &nn->nfsd_serv->sv_pools[i], nthreads[i]);
758 if (err)
759 break;
760 }
761 nfsd_destroy(net);
762 return err;
763}
764
765/*
766 * Adjust the number of threads and return the new number of threads.
767 * This is also the function that starts the server if necessary, if
768 * this is the first time nrservs is nonzero.
769 */
770int
771nfsd_svc(int nrservs, struct net *net, const struct cred *cred)
772{
773 int error;
774 bool nfsd_up_before;
775 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
776
777 mutex_lock(&nfsd_mutex);
778 dprintk("nfsd: creating service\n");
779
780 nrservs = max(nrservs, 0);
781 nrservs = min(nrservs, NFSD_MAXSERVS);
782 error = 0;
783
784 if (nrservs == 0 && nn->nfsd_serv == NULL)
785 goto out;
786
787 strlcpy(nn->nfsd_name, utsname()->nodename,
788 sizeof(nn->nfsd_name));
789
790 error = nfsd_create_serv(net);
791 if (error)
792 goto out;
793
794 nfsd_up_before = nn->nfsd_net_up;
795
796 error = nfsd_startup_net(net, cred);
797 if (error)
798 goto out_destroy;
799 error = nn->nfsd_serv->sv_ops->svo_setup(nn->nfsd_serv,
800 NULL, nrservs);
801 if (error)
802 goto out_shutdown;
803 /* We are holding a reference to nn->nfsd_serv which
804 * we don't want to count in the return value,
805 * so subtract 1
806 */
807 error = nn->nfsd_serv->sv_nrthreads - 1;
808out_shutdown:
809 if (error < 0 && !nfsd_up_before)
810 nfsd_shutdown_net(net);
811out_destroy:
812 nfsd_destroy(net); /* Release server */
813out:
814 mutex_unlock(&nfsd_mutex);
815 return error;
816}
817
818#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
819static bool
820nfsd_support_acl_version(int vers)
821{
822 if (vers >= NFSD_ACL_MINVERS && vers < NFSD_ACL_NRVERS)
823 return nfsd_acl_version[vers] != NULL;
824 return false;
825}
826
827static int
828nfsd_acl_rpcbind_set(struct net *net, const struct svc_program *progp,
829 u32 version, int family, unsigned short proto,
830 unsigned short port)
831{
832 if (!nfsd_support_acl_version(version) ||
833 !nfsd_vers(net_generic(net, nfsd_net_id), version, NFSD_TEST))
834 return 0;
835 return svc_generic_rpcbind_set(net, progp, version, family,
836 proto, port);
837}
838
839static __be32
840nfsd_acl_init_request(struct svc_rqst *rqstp,
841 const struct svc_program *progp,
842 struct svc_process_info *ret)
843{
844 struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
845 int i;
846
847 if (likely(nfsd_support_acl_version(rqstp->rq_vers) &&
848 nfsd_vers(nn, rqstp->rq_vers, NFSD_TEST)))
849 return svc_generic_init_request(rqstp, progp, ret);
850
851 ret->mismatch.lovers = NFSD_ACL_NRVERS;
852 for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++) {
853 if (nfsd_support_acl_version(rqstp->rq_vers) &&
854 nfsd_vers(nn, i, NFSD_TEST)) {
855 ret->mismatch.lovers = i;
856 break;
857 }
858 }
859 if (ret->mismatch.lovers == NFSD_ACL_NRVERS)
860 return rpc_prog_unavail;
861 ret->mismatch.hivers = NFSD_ACL_MINVERS;
862 for (i = NFSD_ACL_NRVERS - 1; i >= NFSD_ACL_MINVERS; i--) {
863 if (nfsd_support_acl_version(rqstp->rq_vers) &&
864 nfsd_vers(nn, i, NFSD_TEST)) {
865 ret->mismatch.hivers = i;
866 break;
867 }
868 }
869 return rpc_prog_mismatch;
870}
871#endif
872
873static int
874nfsd_rpcbind_set(struct net *net, const struct svc_program *progp,
875 u32 version, int family, unsigned short proto,
876 unsigned short port)
877{
878 if (!nfsd_vers(net_generic(net, nfsd_net_id), version, NFSD_TEST))
879 return 0;
880 return svc_generic_rpcbind_set(net, progp, version, family,
881 proto, port);
882}
883
884static __be32
885nfsd_init_request(struct svc_rqst *rqstp,
886 const struct svc_program *progp,
887 struct svc_process_info *ret)
888{
889 struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
890 int i;
891
892 if (likely(nfsd_vers(nn, rqstp->rq_vers, NFSD_TEST)))
893 return svc_generic_init_request(rqstp, progp, ret);
894
895 ret->mismatch.lovers = NFSD_NRVERS;
896 for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) {
897 if (nfsd_vers(nn, i, NFSD_TEST)) {
898 ret->mismatch.lovers = i;
899 break;
900 }
901 }
902 if (ret->mismatch.lovers == NFSD_NRVERS)
903 return rpc_prog_unavail;
904 ret->mismatch.hivers = NFSD_MINVERS;
905 for (i = NFSD_NRVERS - 1; i >= NFSD_MINVERS; i--) {
906 if (nfsd_vers(nn, i, NFSD_TEST)) {
907 ret->mismatch.hivers = i;
908 break;
909 }
910 }
911 return rpc_prog_mismatch;
912}
913
914/*
915 * This is the NFS server kernel thread
916 */
917static int
918nfsd(void *vrqstp)
919{
920 struct svc_rqst *rqstp = (struct svc_rqst *) vrqstp;
921 struct svc_xprt *perm_sock = list_entry(rqstp->rq_server->sv_permsocks.next, typeof(struct svc_xprt), xpt_list);
922 struct net *net = perm_sock->xpt_net;
923 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
924 int err;
925
926 /* Lock module and set up kernel thread */
927 mutex_lock(&nfsd_mutex);
928
929 /* At this point, the thread shares current->fs
930 * with the init process. We need to create files with the
931 * umask as defined by the client instead of init's umask. */
932 if (unshare_fs_struct() < 0) {
933 printk("Unable to start nfsd thread: out of memory\n");
934 goto out;
935 }
936
937 current->fs->umask = 0;
938
939 /*
940 * thread is spawned with all signals set to SIG_IGN, re-enable
941 * the ones that will bring down the thread
942 */
943 allow_signal(SIGKILL);
944 allow_signal(SIGHUP);
945 allow_signal(SIGINT);
946 allow_signal(SIGQUIT);
947
948 nfsdstats.th_cnt++;
949 mutex_unlock(&nfsd_mutex);
950
951 set_freezable();
952
953 /*
954 * The main request loop
955 */
956 for (;;) {
957 /* Update sv_maxconn if it has changed */
958 rqstp->rq_server->sv_maxconn = nn->max_connections;
959
960 /*
961 * Find a socket with data available and call its
962 * recvfrom routine.
963 */
964 while ((err = svc_recv(rqstp, 60*60*HZ)) == -EAGAIN)
965 ;
966 if (err == -EINTR)
967 break;
968 validate_process_creds();
969 svc_process(rqstp);
970 validate_process_creds();
971 }
972
973 /* Clear signals before calling svc_exit_thread() */
974 flush_signals(current);
975
976 mutex_lock(&nfsd_mutex);
977 nfsdstats.th_cnt --;
978
979out:
980 rqstp->rq_server = NULL;
981
982 /* Release the thread */
983 svc_exit_thread(rqstp);
984
985 nfsd_destroy(net);
986
987 /* Release module */
988 mutex_unlock(&nfsd_mutex);
989 module_put_and_exit(0);
990 return 0;
991}
992
993/**
994 * nfsd_dispatch - Process an NFS or NFSACL Request
995 * @rqstp: incoming request
996 * @statp: pointer to location of accept_stat field in RPC Reply buffer
997 *
998 * This RPC dispatcher integrates the NFS server's duplicate reply cache.
999 *
1000 * Return values:
1001 * %0: Processing complete; do not send a Reply
1002 * %1: Processing complete; send Reply in rqstp->rq_res
1003 */
1004int nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp)
1005{
1006 const struct svc_procedure *proc = rqstp->rq_procinfo;
1007 struct kvec *argv = &rqstp->rq_arg.head[0];
1008 struct kvec *resv = &rqstp->rq_res.head[0];
1009 __be32 *p;
1010
1011 /*
1012 * Give the xdr decoder a chance to change this if it wants
1013 * (necessary in the NFSv4.0 compound case)
1014 */
1015 rqstp->rq_cachetype = proc->pc_cachetype;
1016
1017 svcxdr_init_decode(rqstp);
1018 if (!proc->pc_decode(rqstp, argv->iov_base))
1019 goto out_decode_err;
1020
1021 switch (nfsd_cache_lookup(rqstp)) {
1022 case RC_DOIT:
1023 break;
1024 case RC_REPLY:
1025 goto out_cached_reply;
1026 case RC_DROPIT:
1027 goto out_dropit;
1028 }
1029
1030 /*
1031 * Need to grab the location to store the status, as
1032 * NFSv4 does some encoding while processing
1033 */
1034 p = resv->iov_base + resv->iov_len;
1035 svcxdr_init_encode(rqstp);
1036
1037 *statp = proc->pc_func(rqstp);
1038 if (*statp == rpc_drop_reply || test_bit(RQ_DROPME, &rqstp->rq_flags))
1039 goto out_update_drop;
1040
1041 if (!proc->pc_encode(rqstp, p))
1042 goto out_encode_err;
1043
1044 nfsd_cache_update(rqstp, rqstp->rq_cachetype, statp + 1);
1045out_cached_reply:
1046 return 1;
1047
1048out_decode_err:
1049 trace_nfsd_garbage_args_err(rqstp);
1050 *statp = rpc_garbage_args;
1051 return 1;
1052
1053out_update_drop:
1054 nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
1055out_dropit:
1056 return 0;
1057
1058out_encode_err:
1059 trace_nfsd_cant_encode_err(rqstp);
1060 nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
1061 *statp = rpc_system_err;
1062 return 1;
1063}
1064
1065/**
1066 * nfssvc_decode_voidarg - Decode void arguments
1067 * @rqstp: Server RPC transaction context
1068 * @p: buffer containing arguments to decode
1069 *
1070 * Return values:
1071 * %0: Arguments were not valid
1072 * %1: Decoding was successful
1073 */
1074int nfssvc_decode_voidarg(struct svc_rqst *rqstp, __be32 *p)
1075{
1076 return 1;
1077}
1078
1079/**
1080 * nfssvc_encode_voidres - Encode void results
1081 * @rqstp: Server RPC transaction context
1082 * @p: buffer in which to encode results
1083 *
1084 * Return values:
1085 * %0: Local error while encoding
1086 * %1: Encoding was successful
1087 */
1088int nfssvc_encode_voidres(struct svc_rqst *rqstp, __be32 *p)
1089{
1090 return 1;
1091}
1092
1093int nfsd_pool_stats_open(struct inode *inode, struct file *file)
1094{
1095 int ret;
1096 struct nfsd_net *nn = net_generic(inode->i_sb->s_fs_info, nfsd_net_id);
1097
1098 mutex_lock(&nfsd_mutex);
1099 if (nn->nfsd_serv == NULL) {
1100 mutex_unlock(&nfsd_mutex);
1101 return -ENODEV;
1102 }
1103 /* bump up the psudo refcount while traversing */
1104 svc_get(nn->nfsd_serv);
1105 ret = svc_pool_stats_open(nn->nfsd_serv, file);
1106 mutex_unlock(&nfsd_mutex);
1107 return ret;
1108}
1109
1110int nfsd_pool_stats_release(struct inode *inode, struct file *file)
1111{
1112 int ret = seq_release(inode, file);
1113 struct net *net = inode->i_sb->s_fs_info;
1114
1115 mutex_lock(&nfsd_mutex);
1116 /* this function really, really should have been called svc_put() */
1117 nfsd_destroy(net);
1118 mutex_unlock(&nfsd_mutex);
1119 return ret;
1120}